Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. A modern wind turbine typically includes a tower, generator, gearbox, nacelle, and one or more rotor blades. The rotor blades capture kinetic energy of wind using known foil principles. The rotor blades transmit the kinetic energy in the form of rotational energy so as to turn a shaft coupling the rotor blades to a gear system, or if a gear system is not used, directly to the generator. The generator then converts the mechanical energy to electrical energy that may be deployed to a utility grid.
Proper alignment of the meshing teeth of adjacent gears in a gear system, and in particular a planetary gear system, is important for the proper distribution of loads. However, in many current gear systems, various design and operational factors prevent proper alignment of the meshing teeth. For example, manufacturing and design tolerances for the various gears, which typically have involute gear profiles with involute gear teeth, can cause misalignment between the meshing teeth of the adjacent gears. Further, and in particular for gear systems in wind turbines, various components of the gear system such as the carrier experience twisting and/or bending during operation. This twisting and bending is typically caused by loading of an input shaft of the gear system and twisting and bending thereof. Twisting and bending can cause additional misalignment between the meshing teeth of the adjacent gears in the gear system.
Misalignments between adjacent gears in a gear system can have potentially catastrophic results for the gear system and, in wind turbine settings, for the wind turbine itself. For example, misalignments can cause the loads experienced by various gears in the gear system to increase by two or more times the designed loading limits. Thus, the gears that experience this increased loading can become damaged or fail during operation of the gear system, potentially resulting in failure of the gear system.
Thus, an improved gear system, such as an improved planetary gear system, would be desired in the art. For example, a gear system with improved load distribution features would be advantageous.